1. Field of the Invention
The present invention relates to a novel process for producing fiber based on polyarylene sulfide and to thereby obtainable novel multifilament yarn based on polyarylene sulfide.
Polyarylene sulfides are, as will be known, polymers possessing excellent resistance to thermal degradation and a wide range of chemicals. Fibers from these polymers are already known; see for example EP-A-195,422, EP-A-398,094, EP-A-453,100 and JP-A-58-18,409.
2. Description of the Related Art
Specifically designed spinning and aftertreatment processes for producing such fibers are described for example in EP-A-102,536, JP-A-01-239,109 and U.S. Pat. No. 3,539,676. EP-A-102,536 and JP-A-01-239,109 specify spinning takeoff speeds of 900 to 1100 m/min and of not more than 1000 m/min respectively; by contrast, the subsequent drawing conditions are not more particularly specified. On the other hand, U.S. Pat. No. 3,539,676 stipulates spinning takeoff speeds of 20 to 3000 m/min and recommends that no additional drawing be carried out.
The multi-stage drawing of fiber based on polyarylene thioether is described for example in JP-A-01-229,809 and EP-A-398,094.